A rotor of an electric motor is formed by laminating a large number of magnetic steel sheets and a magnet is embedded in an opening provided in an axial direction. Also, end plates are disposed on both end faces of the rotor to prevent the magnet from falling off.
For example, one structure of the end plates is such that a resin end plate is disposed at one end of the rotor and an end plate of an integral structure made up of a resin end ring and a metal end ring is disposed at the other end.